1. Field of the Invention
The present invention relates generally to a non-volatile storage device and more particularly, to a method and apparatus for effectively using a non-volatile storage device, while ensuring the security of the non-volatile storage device.
2. Description of the Related Art
Recently, many types of storage devices have been introduced, such as memory cards using a flash memory as storage means, Universal Serial Bus (USB) memory connectable to a USB port and Solid State Drive (SSD) storage. Recently developed storage devices are characterized by an increased storage capacity, a reduced device size, and an interface detachable from a host device. Therefore, the mobility of storage devices has been enhanced. Further, external hard disks are considered inexpensive storage devices and provide mobility relative to a conventional hard disk installed fixed to a PC.
In addition to storage devices, host devices, which are connected to the storage devices to enable utilization of content stored in the storage devices have also been made smaller and more mobile. In an environment that allows use of digital content stored in a storage device at any time and in any place, content is now distributed in the form of digital data.
However, digital content stored in a storage device is easily duplicated. As such, many techniques for preventing content duplication have been proposed. Although the content duplication prevention techniques are implemented in different manners, the techniques share in common that content utilization is allowed only for authorized persons.
As one of the content duplication prevention techniques, storage devices having a self-authentication function have been developed. For instance, a Secure Digital (SD) card may have a cryptographic function, for data security and a Digital Rights Management (DRM) to control the number of plays and play time, and can be implemented in a secure Multi-Media Card (MMC).
DRM, Content Protection for Recordable Media (CPRM) for SD cards, and Advanced Access Content System (AACS) for Blu-ray Disks™ provide device authentication methods based on Public Key Infrastructure (PKI) or other cryptographic technology.
According to the device authentication methods based on the CPRM and AACS technologies, a device Identifier (ID) unique to a storage device is stored in a read-only area and a cryptographic scheme is applied to the device ID in the process of manufacturing the storage device. A host device then authenticates the storage device using the device ID bound to data stored in the storage device, thereby protecting content.
The storage device may store content corresponding to one or more content applications. Herein, a content application refers to a category into which content can be classified. For example, video content such as movies, game content, and e-book content can be classified respectively into a movie application, a game application, and an e-book application.
Thus, content corresponding to a plurality of content applications can be stored in a single storage device. These content applications stored in the same storage device share the same device ID. Consequently, if the device ID is used inappropriately for any of the applications, the security of the entire system is breached.
That is, since content corresponding to many applications is stored in a storage device using the same device ID irrespective of the security usage of the storage device, occurrence of an inappropriate situation may lead to a discarding of the entire storage device.